The development and fabrication of advanced integrated circuits (ICs) is often carried out by foundries, which may not always be trustworthy. In some instances, the manufactured chips may be modified as compared to the initial design (that is, tampered with) by adding “malicious circuitry” or deleting circuits that can open security issues and/or lead to reliability problems, controlled malfunctioning, and the like. Alterations may be introduced at the silicon manufacturing level, back end of the line wiring level, and/or at the packaging level. These “inserted” or “deleted” circuits cannot be detected through regular electrical screening tests, because they are designed to hide themselves from such tests.